The proposed study is a 12-year follow-up of 321 cocaine- dependent men who were originally admitted in 1988-89 to the West Los Angeles Veterans Affairs Medical Center (WLA-VAMC). These subjects have been previously interviewed at intake and in two follow-up interviews conducted in 1990-91 and 1991-92 as part of a NIDA-funded study (DA04268). These subjects' cocaine use careers from onset of use to treatment entry averaged 11.5 years. The natural history database established by the previous interviews will be supplemented by the proposed work for almost 12 years after treatment admission. The proposed research will represent an unusually long-term follow-up study of cocaine- dependent individuals. The specific aims of the study are: (1) To provide a detailed natural history description of approximately 24-year-long cocaine use careers of cocaine- dependent men; (2) To identify factors that influence relapse and cessation of use over the course of the cocaine use career; (3) To analyze and describe morbidity and mortality among this cocaine-dependent sample; (4) To evaluate the extent of criminal activity, identify specific criminal career patterns in relation to cocaine use, and to assess patterns of institutionalization and legal supervision over the cocaine use career and their effects; (5) To analyze the history of treatment intervention and assess the effects of specific and cumulative treatment episodes on cocaine use. Advanced statistical models (including growth curve modeling) will be applied to assess longitudinal relationships. The study results will inform policy and strategies for treating cocaine use by adding to and refining the understanding of long-term patterns and consequences of cocaine use and other drug use, utilization of drug treatment and other social interventions, and their associated outcomes.